Nanowires are ultra-tiny metal threads that, under specific conditions, grow like plants out of chemical and metal substrates. Now, in this incredible video, you can see what they look like when they're growing. They're pretty much nanoscopic Cthulhu tentacles.

This video is a bright field environmental transmission electron microscopy video of silicon nanowires growing from gold catalyst particles. The dark crystalline shapes initially present in the video are the gold particles. Disilane, a silicon rich gas, feeds nanowire growth. The solid catalyst particles liquefy after being exposed to the disilane early in the video. Eventually, a solid silicon crystal forms in the now liquid catalyst particle. This crystal continues to grow as silicon is continuously deposited into the catalyst from the disilane gas. The new silicon crystal's diameter is restricted by the size of the gold catalyst. This means the silicon can grow in one direction only, forming a nanowire.

Each nanowire is roughly 400 atoms wide. You can find out more about the work Gamalski is doing with nanowires here.

This is the last video in the Under the Microscope series that io9 has been posting in partnership with the University of Cambridge. Under the Microscope is a collection of videos that capture glimpses of the natural and artificial world in stunning close-up. We hope you have enjoyed viewing them as much as we enjoyed making them. You can see all 15 videos in the series here.